errors: make formatparse() an instance method on ParseError

It's just a little simpler this way.

Don't ask me what the "hg: " prefix signifies to the user, I just left
it as it was. I think we should consider changing the prefixes later
(maybe always use "abort: ", or maybe use more specific prefixes in
general).

Differential Revision: https://phab.mercurial-scm.org/D9347

mercurial/chgserver.py

@@ -62,7 +62,6 b' from . import ('
     extensions,
     node,
     pycompat,
-    scmutil,
     util,
 )
 
@@ -508,7 +507,7 b' class chgcmdserver(commandserver.server)'
         try:
             self.ui, lui = _loadnewui(self.ui, args, self.cdebug)
         except error.ParseError as inst:
-            scmutil.formatparse(self.ui.warn, inst)
+            self.ui.warn(inst.format())
             self.ui.flush()
             self.cresult.write(b'exit 255')
             return

mercurial/dispatch.py

@@ -261,7 +261,7 b' def dispatch(req):'
                 ferr.write(_(b"(%s)\n") % inst.hint)
             return -1
         except error.ParseError as inst:
-            scmutil.formatparse(ferr.write, inst)
+            ferr.write(inst.format())
             return -1
 
         msg = _formatargs(req.args)
@@ -469,7 +469,7 b' def _callcatch(ui, func):'
             ui.warn(_(b"hg: %s\n") % inst.message)
             ui.warn(_(b"(use 'hg help -v' for a list of global options)\n"))
     except error.ParseError as inst:
-        scmutil.formatparse(ui.warn, inst)
+        ui.warn(inst.format())
         return -1
     except error.UnknownCommand as inst:
         nocmdmsg = _(b"hg: unknown command '%s'\n") % inst.command

mercurial/error.py

@@ -267,6 +267,20 b' class ParseError(Hint, Exception):'
 
     __bytes__ = _tobytes
 
+    def format(self):
+        from .i18n import _
+
+        if self.location is not None:
+            message = _(b"hg: parse error at %s: %s\n") % (
+                pycompat.bytestr(self.location),
+                self.message,
+            )
+        else:
+            message = _(b"hg: parse error: %s\n") % self.message
+        if self.hint:
+            message += _(b"(%s)\n") % self.hint
+        return message
+
 
 class PatchError(Exception):
     __bytes__ = _tobytes

mercurial/scmutil.py

@@ -142,18 +142,6 b' def nochangesfound(ui, repo, excluded=No'
         ui.status(_(b"no changes found\n"))
 
 
-def formatparse(write, inst):
-    if inst.location is not None:
-        write(
-            _(b"hg: parse error at %s: %s\n")
-            % (pycompat.bytestr(inst.location), inst.message)
-        )
-    else:
-        write(_(b"hg: parse error: %s\n") % inst.message)
-    if inst.hint:
-        write(_(b"(%s)\n") % inst.hint)
-
-
 def callcatch(ui, func):
     """call func() with global exception handling